1887

Abstract

strain EBF65/65 harbours a cryptic plasmid, pAV2, which has been shown by electrophoretic separation on agarose gels to have a molecular mass of approximately 13.5 megadaltons (Md). Transfer of the previously described sex factor pAV1 (Hinchliffe & Vivian, 1980, ) from the hospital strain JC17 into strains possessing pAV2 occurs only at a low frequency, whereas transfer to similar strains lacking pAV2 occurs at a much higher frequency. In EBF65/65, pAV1 may be present in strains possessing or lacking pAV2; pAV1 strains lacking pAV2 correspond to strains previously described as pAV1a (Hinchliffe & Vivian, 1980) whereas pAV1 strains which also possess pAV2 correspond to pAV1b strains. The genetic evidence presented here is consistent with the hypothesis that pAV2 specifies a host restriction and modification system that is active against pAV1. Physical evidence from agarose gel electrophoresis indicates that pAV1 corresponds to a band of approximately 85 Md in strain JC17. The corresponding band in strains of EBF65/65 is difficult to distinguish because of the presence of a further cryptic plasmid band of approximately 88 Md, designated pAV3. A small cryptic plasmid of approximately 6 Md, designated pAV4, is reported for EBF65/65.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-121-2-411
1980-12-01
2019-10-20
Loading full text...

Full text loading...

http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-121-2-411
Loading
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error